Spring-force connecting terminals such as these are known in many forms. An electrical conductor is pushed against a busbar section by a clamping section, by the spring force of a clamping spring, and in this way makes an electrically conductive contact between the busbar section and the clamped-on electrical conductor.
In particular in order to remove an electrical conductor, the clamping spring must be moved against its spring force, and the clamping point must be opened. This is done using operating tools, such as screwdrivers, which are inserted into suitable operating openings, or their operating members which are fitted in the insulating-material housing of the connecting terminal.
By way of example, DE 202 08 724 U1 discloses a connecting terminal having an essentially C-shaped clamping spring, which is operatively connected to an operating lever and is fixed onto a busbar in the form of a cage. When the lever is operated, the conductor insertion opening is opened against the spring force of the clamping spring, thus allowing a conductor to be inserted. When the operating lever is returned, the electrical conductor is clamped against the busbar, in order to make an electrically conductive connection.
EP 1 622 224 B1 discloses a connecting terminal in which the clamping edge of the clamping limb of a clamping spring forms a clamping point with a busbar which is opposite the clamping edge. The clamping limb can be lifted off the busbar against the spring force by an operating lever which is held such that it can pivot in the insulating-material housing, in order to open a conductor insertion opening, or to release a clamped conductor. In the process, the lever presses on the clamping limb, with tensile forces acting in the housing sides, walls and housing intermediate walls.
DE 38 22 980 A1 discloses a connecting terminal in which a spring in the form of a fork is sprung apart and opened when an operating lever is opened, thus allowing an electrical conductor to be inserted. In order to close the clamping clip, the operating lever presses against a limb of the spring, which is in the form of a fork, in the opposite direction to the spring force, and clamps the electrical conductor, in this way to make an electrical contact. In this case, the clamping force is applied by the operating lever.
DE 10 2007 050 936 A1 discloses a connecting terminal having a cage tension spring, which has an opening in the clamping limb. A busbar which rests on the holding limb projects through the clamping limb. On the side of the holding limb facing away from the busbar, a curved spring area of the cage tension spring is operatively connected to an operating lever. The clamping point between the clamping limb and the busbar can be opened with the aid of the operating lever, which produces a compression force on the spring.